The utilization of second generation feedstocks for the production of platform chemicals by filamentous fungi
The depletion of petroleum and other platform chemical resources are a global concern; therefore alternative substrates must be identified to replace these current sources. Thus allowing research in fungal biotechnology to prosper, as filamentous fungi can utilize second-generation feedstocks or agricultural waste to produce these petroleum derived platform chemicals. This research focuses on the ability of filamentous fungi to use different second-generation feedstocks such as wheat bran and sugar cane bagasse to generate platform chemicals of interest, namely being itaconic acid (IA) and other organic acids of interest, such as citric acid. This study focused on the metabolite producing capabilities of Aspergillus terreus, initially in a shake flask fermentation environment and then in an Airlift Bioreactor environment utilizing hydrolyzed wheat bran and sugar cane bagasse as a substrate source to produce metabolites of interest. The initial shake flask fermentation experiment involved inoculation and incubating A. terreus in hydrolyzed wheat bran with additional minerals at 30°C for 5 days at a pH range of between 3-4. The result yielded itaconic acid and citric acid concentrations of 1.01g/l and 6.23g/l at their peaks, respectively. The airlift bioreactor was run for 16 days with a constant pH range between 3-4, at a temperature of 30°C with a dissolved oxygen level of 20g/l. The result of the study yielded a high itaconic acid and citric acid concentration peaking at 59.4 g/l and 59.2 g/l, respectively.